What is a Brake Master Cylinder Pump?The master cylinder is designed to put hydraulic pressure on the brake pads. This is done by a rod that is engaged when the brake is applied, this in turn operates two pistons that push fluid to the brakes from the master cylinder. When it is not working properly the braking system can fail.

Sign/Symptoms of a bad master cylinderLow brake pedal Low brake pressure, the brake pedal goes to the floor or close to it. This is one sign though that should not be ignored. The Brake master cylinder will be the number one culprit. This is because it is always best to start at the beginning and work your way through the rest of the system.

If the master cylinder is suspected then have it checked by a professional.

The other two things that can cause low brake pedal are usually:

The other cause of a brake pedals going to the floor would be air in the brake lines. This can be caused when adding fluid to quickly which can form bubbles in the lines. Brake fluid should never be shook before adding and should be added very slowly.

The line itself could be bad either leaking around the line or ballooning in one area or another. This will also cause the brake pedal to not work properly and even go to the floor.

LeakageLeakage around the master cylinder is a bad sign this should be checked any time the oil or transmission fluid is checked. The problem here could be a bad diaphragm or the lid may not be on the fluid level holder correctly.

How bad the leak is can be determined by monitoring the amount of brake fluid that is used. Never take this for granted as this puts not only your life at stake but someone else's as well. When in doubt have a professional check the problem.

The brakes on one's vehicle should not be taken lightly. Inspecting the master cylinder from time to time for fluid level and leakage can help head off a possible problem. Doing things yourself can save more than money in this instance it can save lives.